If you are going to be heavy on the bow, perk it out.
Focus on damage perks mainly, and whatever else seems interesting or useful to you. I like ranger and quick shot.
You don't have to put a lot of perks into one-handed because sneak kills do tons of damage. Unless of course you want to fight toe to toe, then focus on damage perks and blade perks. Only do the dual savagery and dual fury if you dual wield a lot, other than that its not worth it. But it sounds like you use a spell in one hand.
Destruction is pretty self explanatory. You could always specialize in one element if you are wanting to save perks.
In sneak you don't really need all the fancy forward rolling, muffling, etc perks on the left. Focus on damage perks for bows and daggers and the first perk that raises your effective sneaking.